Automatically controlled abrading machine



March 17, 1936. R L

AUTOMATICALLY CONTROLLED ABRADING MACHINE 5 Sheets-Sheet 1 Filed Aug.,23, 1933 G. 5 RAYMOND A. COLE F7 WITNESSES March 17, R} COLEAUTOMATICALLY CONTROLLED ABRADING MACHINE Filed Aug. 28, 1953 3Sheets-Sheet 2 21 F715. 2 RAYMOND A. CULE WITNESSES Mum Coley March 17,1936. R. A. COLE AUTOMATICALLY CONTROLLED ABRADING MACHINE 3Sheets-Sheet 5 Filed Aug. 28, 1953 W we A We NU w Z w WITNESSES IPatented Mar. 17, 1936' v AUTOMATICALLY CONTROLLED MACHI Raymond A.Cole, Worcester, Mass., assignor to Norton Company, Worcester, Mass., acorporation of Massachusetts Application August 28, 1933, Serial No.687,030

22 Claims.

This invention relates to automatically controlled abrading machines,and more particularly to an automatic control mechanism for controllingthe extent of the abrading action and producmg work pieces ofpredetermined sizes. It is particularly applicable to machines, hereintermed abrading machines, in which a flat or radial face of one abradingelement or of two opposed abrading disks or laps are utilized for sizingone or a plurality of flat or cylindrical pieces of work.

, This mechanism is applicable to lapping machines of the type shown inthe patent to Indge et al. No. 1,831,958 or to the rotary type surfacegrinding machine in which the flat face of a rotary abrading disk grindswork on one side while it is supported on a rotary chuck, as well as tothe double opposed disk grinding machines of the Gardner type, such asshown in the Gardner Patent No. 1,589,593. In a lapping machine, aplurality of flat or cylindrical work pieces are mounted in a workcarrying cage between two opposed laps or disks, the upper one of whichis movable downwardly to engage and cause the work pieces to be lapped.The laps or disks and the cage are so moved'relatively that the workpieces are caused to travel through irregular ever changing pathsbetween the opposed faces of two disks, either or both of which may berotated or be held stationary;

It has been proposed, as shown in the patent to Belden and Cole .No.1,911,552 dated May 30, 1933, to employ an electrical control device ina grinding machine which serves to remove the wheel from the work whenthe latter has reached a measured size. It has also been proposed tostop the downward movement of the upper lap of a lapping machine when ithas reached a stop, but this has notserved to stop the cage rotation,

which goes on until the operator stops the machine. Also a device hasbeen suggested for stopping the cage'rotation when the workhas beenmoved through a predetermined number of revolutions, but this has notinsured reducing the work to a predetermined size.

The primary object of this invention is to provide such an abradingmachine in which the Work is automatically sized,-and in which therelative movement of the work and abrading disk or disks is socontrolled as to produce not only the desired finish but also accuracyin dimensions.

A further object is to provide such a machine with a control mechanismwhich not only controlsthe movement of the abrading disk towards thework, in that it automatically causes their separation, but also stopsthe relative movement of the disk and work after the abrading operationhas proceeded to a predetermined extent.

It is another object of this invention to provide a control mechanismincluding a time delay device actuated by the relative movement of thework and abrading lapping disks to separate them after a predeterminedlapping operation.

Other objects will be apparent from the following disclosure. Oneembodiment of this invention has been illustrated in the drawings, inwhich like reference numerals indicate like parts.

Fig. 1 is a side elevation of an improved abrading machine embodyingthis invention, having parts broken away to more clearly show the 5construction;

Fig. 2 is a diagrammatic view, showing diagrammatically the drivingmechanism for the abrading disk elements and the cage, as well as thewiring diagram for the electrical control system;

Fig. 3 is a cross-sectional view, on an enlarged scale, takenapproximately on the line 3-3 of Fig. 1, showing the manually operableand the electrically actuated power and manual control mechanism forraising and lowering the movable abrading element;

Fig. 4 is a fragmentary elevation, on an enlarged scale, of thereversing switch for controlling the reversible motor for raising andlowering the upper abrading disk;

Fig. 5 is a fragmentary elevation of the mercury switch, which serves tobreak the circuit and thereby render inefiective the, electrical controlapparatus when the abrading disks are in a separated position;

Fig. 6 is a fragmentary sectional view, on an enlarged'scale, of thecontact mechanism in the electrical control system for governing theex-' tent of the abrading operation; and

Fig. '7 is a fragmentary side elevation of the upper part of Fig. 6, onan enlarged scale, to show the support and adjustment for the movablecontact member.

The embodiment of this invention illustrated Al in the drawingscomprises two opposed rotatable abrasive disks or laps and a Work cagehaving a plurality of work receiving apertures therein which issupported between the disks and arranged to simultaneously abrade aplurality of 50 work pieces therebetween. The work carrying cage isarranged to be simultaneously rotated and revolved by a power operatedmechanism to carry the pieces of work through irregular paths. Theabrading disks are mounted so that they 56 may be moved relativelytoward and from each other by a power actuated mechanism. In accordancewith this invention, I provide such a machine with a control device,preferably electrically operated, and suitable mechanism which serveswhen a control member is actuated by the relative approaching movementof the disks to stop the abrading operation. This mechanism serves toseparate the disks automatically when the desired work size has beenattained and it preferably acts to stop the relative movement of thecage and disk. In the specific form illustrated, a time delay devicewhich is preferably set into motion by the approaching movement of thedisk or disks towards the work causes the work to be abraded for apredetermined period after the control device has been renderedeffective. The preferred embodiment illustrated in the drawingscomprises two opposed rotatable abrasive disks and a work cagetherebetween which is arranged to be simultaneously rotated and revolvedby a power operated mechanism to carry the work pieces through irregularpaths. The two abrading disks are so mounted that they may be movedrelatively toward and from each other by'a power actuated mechanism. Anelectrical control apparatus is provided which is rendered effective bythe relative approaching movement between said disks and serves toactuate a time delay device which in turn causes the power mechanism toautomatically separate the disks after a predetermined abrading periodand to simultaneously stop the rotation of the disks and the cage.

As illustrated in the drawings, the improved grinding or abradingmachine comprises a base in which rotatably supports a lower abrasivewheel II for rotation upon a vertical spindle i 2. The base is providedwith an upwardly extending projection i3 which supports an abrasive diskl4 on a vertically mounted rotatable spindle l5. To facilitate arelative approaching and receding movement between the abrading membersI I and i4, the spindle is preferably supported in a vertically movableslide 16 which is supported in a dovetailed slideway I! in the upwardlyextending projection i3 of the base In. By movement of the slide IS in avertical direction, the upper abrading element may be caused to movetoward and from the lower abrading element H to reduce the work piecesto the required size.

Feeding device It is desirable to provide a suitable mechanism forraising and lowering the movable abrading disk to bring the disk intoengagement with the work and to remove it therefrom after the operationhas been completed, as well as to provide a. suitable means for feedingthe abrading disk with the desired pressure to produce the desiredabrading action between the abrading disks and the opposed faces of thework piece. As illustrated in the drawings, the slide it is providedwith a rack 20 meshing with a pinion 2i on a shaft 22 which is rotatablymounted in the projection i3 of the base it). The shaft 22 carries aworm gear 23 meshing with a worm 24. The worm 24 is slidably keyed to ashaft 25 and is held in position by the opposed springs 26 and 21 whichsurround the shaft and are interposed between the ends of the worm 24and a bearing 28 and an enlarged portion 29 on the other end of theshaft 25. The other end of the shaft 25 is provided with a hand wheel30, by means of which the shaft 25, the worm 24, worm wheel 23, shaft 22and pinion 2 i, may be turned to move the'rack 20, slide i6, and therebytransmit a vertical motion to the upper disk i4, either relativelytoward or from the lower lap, as desired.

It is desirable to provide a suitable power actuated mechanism forrapidly raising and lowering the upper abrading disk with the minimumamount of exertion required on the part of the operator. Such amechanism, as illustrated in the drawings, may comprise an electricmotor 32 mounted on a support 33 within the base. The motor is providedwith a pinion 34, which is connected by a. link chain 35 with a sprocket36 on the end of the shaft 25. In the preferred construction, thesprocket 36 is mounted as one element of a centrifugal clutch 31 whichserves to connect the sprocket 36 to rotate the shaft 25. By utilizing acentrifugal clutch, for the power drive, it eliminates the necessity ofrotating the power driven mechanism when the upper abrading disk ismanually adjusted. The motor 32 is prcferably of the reversible type sothat the direction of movement of the upper disk may be readily variedby means of a reversing switch 38 which is controlled by a manuallyoperable lever 39. Movement of the lever 39 into position 39a serves toconnect the motor so as to raise the upper abrading disk to cause theseparation or receding movement between the two abrading disks.Similarly, moving the lever 39 into position 3% serves to lower theupper abrading disk and to cause an approaching movement between the twoabrading disks and also relative to the work pieces 40.

Work carrying cage and driving mechanism A plurality of work pieces 40are mounted in a work carrying cage 4i which is carried by driving pins42 which are rotated and revolved by means of a gear mechanism 43. See,for example, the cage operating mechanism in the prior patent to IndgeNo. 1,610,527, dated December 14, 1926. This cage operating mechanism isnot a part of the present invention, and consequently has not beenillustrated in detail. For further reference to the cage operatingmechanism, reference should be had to the above-mentioned patent.

Lap rotating mechanism In the operation of the improved or abradingmachine, the abrading disks II and H are arranged for rotation relativeto each other. Either one or both of the abrading disks may be rotated,as desired, depending upon the nature of the work to be finished on themachine. In the preferred construction, both of the abrading disks IIand I4 are simultaneously rotated in the opposite direction and atsuitable speeds to produce the desired operating action. As illustratedin the drawings, a main driving motor 50 is provided to serve as a primemover for rotating the abrading disk and also for controlling themovement of the cage 4| to produce the desired abrading action. Themotor 50 is provided with a pulley 5i which in turn drives a belt 52which passes over a pulley 53 on a cross shaft 54. The pulley 53 isfreely rotatable on the shaft 54 and is integrally connected with aclutch member 55 which is also free to rotate on the shaft 54. A movableclutch member 56 is slidably keyed to the shaft 54 and is arranged to beengaged or disengaged with the member 55, by means of a manuallyoperable lever 51 which is connected by a link 58 to move the clutchshifting rod 59 which is connected at its other end by a suitable clutchshifting member 50 to the movable clutch member 56. The lever 51 ispivotally supported'on a stud 6| which is flxed to the base l8. Theshaft 54 is provided with a worm G3 which meshes with a worm gear 64 torotate the support 12 for the lower abrading disk, II. The shaft 54 isalso provided with a pulley 68 which drives a belt 61 passing around apulley 68 on a shaft 69. The shaft 89 is provided with a worm l8 meshingwith a worm gear" on the vertical spindle I to transmit a rotary motionto the spindle l5 to rotate the abrading disk l4.

Reversing switch The reversing switch 38. is preferably provided with asuitable actuating mechanism which may be automaticallyactuated by thevertical movement of the slide it. As'illustrated in the drawings, theswitch 38 -is provided with a lever 15 which is connected to a gearsegment 16, gear 11 and gear 18 with a gear segment 19 on the manuallyoperable lever 39. By utilizing the gearing above mentioned, the lever15 will be moved in timed relation with and in the same direction as thelever 39. Thus, if it is desired to move the upper abrading disk towardthe lower abrading disk, the lever 39 is moved into a position 39b whichin turn serves to move the lever 15 into position 15b. Similarly, whenit is desired to move the upper disk in an upward direction, the lever39 is moved into position 390. which in turn through the gear trainserves to move lever 15 into position 15a; In order that the powerdriving mechanism may be automatically disconnected to stop the verticalmovement of the slide it, either when approaching or receding from thelower 'sk, a suitable adjustable dog mechanism is provided comprising alower adjustable dog 88 and an upper adjustable dog 8| which are mountedon a projection 82 of the base. It will'be readily apparent from theforegoing description that when the slide I6 is moved downwardly bymanually movingthe lever 39 into position 39b, the slide l8 andreversing switch 38 will move downwardly until the lever 15b engages thedog 88 which serves upon continued downward movement of the slide torock the reversing switch into a neutral position, as shown in fulllines in Fig, 4. Similarly, when the upper disk is moved in'an upwarddirection, the adjustable dog BI is arranged to engage the lever 15 whenin position 15a, and similarly move the reverse switch into a neutralposition and thereby stop the upward movement of the disk l4. 7

Pressure device As illustrated in the drawings, a slightly differcuttype of pressure device has been illustrated which is more readilyadaptable to an improved abrading machine. As illustrated in Fig. 3, theworm 24 is held in its central or normal position by'means of theopposed springs 26 and 21 which surround the shaft 25. The slide it maybe moved downwardly into operative relation with the work to cause anabrading action, either by means of the motor 32 which moves the sliderapidly into position, but is preferably moved into contact with thework by the manually operable wheel 38. Rotation of the hand wheel 38rotates the shaft 25, the worm 24, worm gear 23, shaft 22, gear 2|, tomove the rack 28 and 'slide I 6 in the desired direction. After the'upper disk I4 engages the surface of the work, the operator continues torotate the manually operable wheel 38, during which movement the wormgear 23 is relatively stationary due to engagement of disk I4 with thework, and worm 24 serves as a screw threaded member and rotates andmoves axially relative to the worm gear, compressing the spring 26 tothe desired extent to give the required pressure for the abradingoperation. In order that the operator may readily turn the wheel 30 toduplicate the pressure on successive operations, a dial indicator 85 isprovided mounted on the projection l3 of the base l8. A collar 88 isslidably mounted on the shaft 25 and is held against the end of the worm24 by means of a spring 21. A pivotally mounted lever 81 has one end 88arranged to engage the end of the sleeve 86 and its other end connectedto a plunger 89 which is connected to operate the dial indicator 85.During the normal vertical movement of the slide l8 in a downwarddirection, the sleeve 86, lever 81, plunger 89 and dial indicator 85 arestationary and inoperative. When the upper abrading-disk 14 engages theupper surface of the work and continued rotation of the hand wheel 38serves to tension the spring 26 to exert a pressure betweenthe abradingelements and the work, the dial indicator and its actuating lever andplunger are operative to register or indicate the tension of the spring26. On successive abrading operations, the hand wheel 38 is turned untilthe dial indicator reads a predetermined pressure which has been foundby experience to be suitable for the operation being performed. 7

Electrical control In order to attain one of the primary'objects of thisinvention, a suitable control apparatus is provided for regulating theextent of the abrading operation so that duplicate pieces of work may beproduced on successive operations with a minimum amount of attention onthe part of the operator. In the preferred construction, a suitableelectrical control apparatus is provided which serves to regulate theextent of the abrading action after the abrading disks are brought intooperative engagement with the work to be abraded. It is not onlydesirable but essential that the abrading disks be automaticallyseparated after a predetermined abrading operation has been completed,and also that the relative rotation of the abrading elements and thecage be automatically stopped when the abrading disks recede to aninoperative position. One form of this control system is illustrated inthe drawings, in which the downward movement of'the slide l6 serves toeither make or break a circuit to actuate the time delay device whichpermits a predetermined abrading operation with the abrading disksengaging the work at the desired predetermined pressure beforeautomatically separating them from engagement with the work. Ifdesirable, a visible indicating device, such as a dial indicator 98, maybe provided to indicate when the upper abrading disk has approached thelower abrading disk and work to a predetermined extent. The dialindicator is carried by the vertically movable slide I6 and is arrangedto be actuated by a slidable plunger OI which is journalled in suitablebearings 92 and 93 in the slide I6. When the slide I6 moves downwardly,a head 94 on plunger 0| engages a stop 95 which is fixed to thebase ofthe machine. As the slide continues moving in a downward direction, theplunger SI moves upwardly and actuates the dial indicator whichindicates the approach of the upper abrading disk toward the lowerelement during the abrading operation. In the preferred construction, asuitable automatic control is provided which is independent of the dialindicator and serves to automatically control an electrical system forautomatically terminating the abrading action after the work has beenreduced to a predetermined extent.

The dial indicator is preferably adjustably positioned on the slide I6so that the mechanism may be readily adapted to set the machine up forabrading various sizes of work. As illustrated in Fig. 6, the bearings92 and 93 as well as the indicator 90 are supported by an adjustablesleeve I00. The sleeve I00 has a thread IOI on its periphery meshingwith an internally threaded sleeve I02 which is supported within anaperture in the slide I6. To facilitate vertical adjustment of the dialindicator and its actuating mechanism, the periphery of the sleeve I02is provided with a worm gear I03 meshing with a worm I04 which ismounted on a shaft I05. The shaft I05 is also provided with a manuallyadjustable wheel I06 which serves to rotate the sleeve I02 and therebyadjust the position of the sleeve I00 and thereby position the dialindicator in setting up the machine for a given operation.

The sleeve I00 carries a bracket I06 which supports an electricalcontrol head I09. The head I09 is provided with a central verticallymovable plunger IIO which engages and operates with the plunger II I ofthe dial indicator. The upper end of the plunger IIO engages the end ofan adjustable screw H2 in a bell crank lever II3 which is supported by aknife edge support II4. As illustrated in the drawings, the electricalcontrol head is illustrated for use in a break circuit, the long arm II5 serving as one of the contact members and the contact II6 serving asa fixed contact member which is supported within the head I09. The armH5 is held in contact with the member II6 by means of a spring IIIexerting a pressure on a short arm I I8 of the bell crank I I3 so as tohold the contact points in engagement with each other. It will bereadily apparent from the foregoing disclosure that the head I09 iscarried by and moves with the vertical slide I0. As the slide movesdownwardly to bring the upper abrading disk I4 into engagement with thework to abrade a plurality of work pieces, the gage head I09 also movesdownwardly until the plunger head 94 engages the fixed stop 65 on thebase and continued movement raises the plunger IN, the dial indicatorplunger III, and the control head plunger II 0, so as to rock the bellcrank II3 and break the circuit between the contact members H5 and H6.

In order to prevent arcing and a consequent pitting of the contactpoints during continued operation, it is desirable to provide a lowenergy current at the make and break point in the control head. Thisfeature is not part of the present invention, but is clearly defined andcovered by the prior patent to Cole et al. No. 1,911,552, dated May 30,1933. A suitable adjusting screw I I9 is provided to adjust the position01 the contact member II6 relative to the contact arm I I5.

As illustrated in the drawings, power .is provided from any suitablesource, such as indicated by the power lines I25. This source may beeither of a direct or alternating current, but for the sake ofillustration, an alternating current source has been indicated. Thecurrent from the source I25 flows through a transformer I26 to step thecurrent down to a low energy current suitable for the control head.Current passing from the transformer I26 passes through arectifier I21which changes the current from an alternating to a direct current forapplication to the electric control head.

It is desirable that no current be flowing through the head when theupper abrading disk is in a raised position. To accomplish this, amercury switch I30 is mounted on a rotatable support I3I pivoted on astud I32, which is fixed to the upwardly extending portion I3 of thebase I0. The member I3I is provided with an outwardly extending stud I33arranged in the path of an adjustable stop I34 carried by the verticallymovable slide I6. The stop I34 is adjustable in an elongated slot I35and arranged so that it may be adjusted vertically so that when the headI6 is raised to an inoperative position, the pin I33 strikes the stopI34 and rocks the member I3I into the' position illustrated in Fig. 5 sothat the mercury switch I30 is tipped to break the circuit and preventthe flow of current through the electrical control head.

At the start of the abrading operation, the operator causes a downwardmovement of the head, either manually or under power, allows the stopI34 to recede and the member I 3I to rock, tipping the mercury switch tomake the circuit and permit current to flow through the transformer andrectifier and the control head to energize magnet I40 whichserves tomove the member I into position I4Ia, thereby breaking a high energycircuit which operates a time delay relay I42. The time delay relay I42is of a standard commercial type, preferably. one in which the parts maybe set so that the relay trips after actuation when a predeterminednumber of seconds or minutes have elapsed. The time delay relay isconnected to energize a relay I43 which in turn serves to simultaneouslyenergize a solenoid I44 and also a solenoid I45. The solenoid I44, asillustrated, is of the pull-type and is arranged to actuate thereversing switch 38 so as to cause an upward or receding movement of theupper abrading disk when the abrading operation has proceeded to apredetermined extent. The solenoid I45 is operatively connected by alink I46 to the control lever 51 so that when it is energized, it servesto move the lever 51 into the position as illustrated in Fig. 2, therebymoving the clutch member 56 into a disengaged position, as illustratedin Fig. 2, to stop the relative rotation of the abrading disks and thecage simultaneously with the separation or receding movement between theabrading disks.

If it is desired to operate the machine without the electrical sizecontrol apparatus, the operator may swing the stud I33 in acounterclockwise direction, as indicated in Figs. 1 and 5, into positionI33a, thus inverting the mercury tube switch and rendering ineifectivethe electrical control apparatus. In this position of the switch, themachine may be operated under manual control, and the upper abradingdisk fed manually by means of the hand wheel 30, or the upper disk maybe raised or lowered by power under manual control of the reverse switch38.

The operation of this mechanism will be readily apparent from theforegoing disclosure. Assuming the adjustments of the various mechanismto have been previously made, and that the parts are in the position asillustrated in Figs. -1, 2 and 6, the manually operable control lever 51is moved in a clockwise direction (Figs. 1 and 2) to engage the clutchmember 56 so as to cause a relative rotation between the abradingdisksand to cause an irregular motion of the cage therebetween. Thereverse switch control lever 39 is moved into position 3% to start themotor 32 and cause a downward movement of the upper abrading disk. Thedownward movement of the abrading disk I4 continues until the adjustabledog strikes the lever 15b and moves the reverse switch into a neutralposition to stop the downward feed under power just prior to the upperabrading disk I4 engagingthe surface of the work. The hand wheel 30 isthen rotated to move the abrading disk I4 into operative engagement withthe work, and the rotation of the wheel 30 continues until the worm 24compresses the spring 26 so that the dial indicator 85 registers thepredetermined desired pressure for the abrading operation. The abradingoperation continues, and the abrading disk I4 moves downwardly under thetension of the spring 26 until the head 94 of the electrical controlapparatus engages the fixed stop 95 on the base and upward movement ofthe plunger 9| serves to break the contact between the contact membersH5 and H6 in the control head I09. Breaking of the contact serves todeenergize the relay I40 and allows the pivotally mounted member I4I tomove into the position as illustrated in full lines in Fig. 2 so as toclose the high energy circuit and thereby start actuation of the timedelay relay I42, the time delay relay having been previously set to tripin a predetermined number of seconds or minutes after the contacts H5and H6 have been broken. When the relay I42 operates after' theprescribed abrading period, electric circuit including relay I43 isenergized, thereby closing the circuit and energizing the solenoid I44which serves tothrow the reverse switch, swinging the handle 39 intoposition 3911 to cause a relative separating movement between theabrading disks, and at the same time energizes the solenoid I 45 'toswing the main control lever 51 into the position illustrated in Fig. 2to disengage the clutch 56 and thereby stop the relative rotation of theabrading disks II and I4 and the motion of the cage 4!. The upward orreceding movement of the abrading disks I4 continues until theadjustable pin I34 on the slide I6 engages the stud I33 and rocks themember I3I and the mercury tube switch I30 into the position illustratedin Fig. 5, breaking the circult to the transformer I26, therebyrendering ineffective the electric size control head I09.

When the downward movement of the abrading disk I4 is started bymanipulation of the reverse switch lever 39. the electric size controlhead is ineflective until the pin I34 moves downwardly from the positionindicated in Fig. 5, al lowing the member I3I and the mercury tubeswitch I30 to rock until the circuit is closed, permitting current toflow through the transformer I26, rectifier I21 and to the electric sizecontrol head I09 so as to energize the magnet I40 and swing thecontactor MI into position !4Ia. The contactor'I4I remains in positionMia under the influence o! the electromagnet I40 until the continueddownward movement of the upper abrading disk I4 breaks the circuit byseparating contacts H5 and H6.

Having thus described the invention, what is claimed as new and desiredto secure by Letters Patent is:

1. An abrading machine comprising a rotatable abrading disk having aflat operative surface and an opposed rotatable work carrier for holdinga plurality of work pieces in operative relation with said disk, meansto rotate said abrading disk and work carrier, means to cause a relativeapproaching and receding movement between said abrading disk and workcarrier, and a control device actuated in timed relation with theapproaching movement of said a rading disk to automatically separatesaid disk and carrier and to stop the rotation of the abrading disk andthe work carrier after a predetermined abrading operation.

2. An abrading machine comprising a rotatable abrading disk, an opposedrotatable work support, means to rotate the disk and the work supportfor an abrading operation, means whereby the disk and the work may moverelatively towards each other, means including a measuring device whichcontrols the disk movement and serves to automatically stop the relativeapproach of the disk towards the work at a predetermined position, andmeans actuated in timed relation with the operation of the measuringdevice which serves to stop the rotations of the disk and the worksupport automatically after the stoppage of the disk approachingmovement.

3. A machine of the type covered by claim 2 in which a time delay deviceserves to permit an abrading operation after the stoppage of the diskfeed and before the work and disk rotations are stopped.

4. An abrading machine having a rotatable abrading disk and a workcarrier opposed thereto which is arranged to support a plurality of Workpieces in operative relation with said abrading disk, mechanism to causea relative approaching movement between said abrading disk andcarrier tobring said disk into operative relation with the work to be abraded,means to apply a predetermined pressure between said abrading disk andthe work, and means automatically actuated when said disk and carrierhave reached a predetermined relative position which serves toautomatically separate said disk and carrier after afurtherpredetermined period of abrading.

5. An abrading machine having a rotatable abrading disk and a workcarrier opposed thereto which is arranged to support a plurality of workpieces in operative relation with said abrading disk, power actuatedmechanism to cause a relative approaching movement between said abradingdisk and carrier to bring said disk into operative relation with saidwork to be abraded, means to apply a predetermined pressure between saidabrading disk and the work, and

means automatically actuated when said disk and carrier have reached a.predetermined relative position which serves to automatically separatesaid disk and carrier after a further predetermined period of abrading.

6. An abrading machine comprising two opposed disks movable relativelytowards and from each other, a carrier for a plurality of work piecestherebetween. means for moving the carrier and the disks relatively soas to cause the work pieces to travel through irregular paths whilebeing abraded by the opposed disks, means to cause said disks torelatively approach each other and engage the work, mechanism to cause aseparation of the disks and a control device operated automatically inresponse to movement of the disks to a predetermined distance from eachother which causes said mechanism to separate the disks and stop therelative movement of the disks and carrier after a predetermined lappingoperation.

'7. A machine of the type covered by claim 6, in which a time delaydevice operates when the disks have reached predetermined positions tocause the work to be abraded for a predetermined period thereafter andbefore the disks are separated.

8. An abrading machine having two opposed abrading disks which arerelatively movable towards and from each other, and a cage for amultiplicity of work pieces therebetween comprising means for moving thecage and disks relatively to cause the work pieces to travel throughirregular paths between said disks, power actuated means to cause arelative approaching movement between said disks to move the disks intoand out of operative engagement with the work pieces, and anelectrically operated sizing device to cause the power actuated means toseparate said disks after a predetermined period of abrad- 9. Anabrading machine having a rotatable abrading disk and a work carrieropposed thereto which is arranged to support a plurality of work piecesin operative relation with said abrading disk, power actuated mechanismto cause a relative approaching movement between said abrading disk andcarrier to bring said carrier into operative relation with the work tobe abraded, means to apply a predetermined pressure between saidabrading disk and the work, and automatically actuated means controlledby the approaching movement between said disk and carrier toautomatically separate said disk and carrier after a predeterminedperiod of abrading.

10. An abrading machine having a rotatable abrading disk and a rotatablework carrier opposed thereto comprising means to relatively rotate saidabrading disk and work carrier, a power actuated means to cause arelative approaching and receding movement between the abrading disk andwork carrier, an electrically actuated control device to control themovement of said abrading disk, means including a pair of contactmembers actuated by the relative approaching movement between said diskand the carrier to actuate said control device after the abradingoperation has continued to a predetermined extent, means actuated by thecontrol device to cause, a receding movement between the carrier and thedisk and to stop the relative rotation of the disk carrier.

11. An abrading machine having a rotatable abrading disk and a workcarrier opposed thereto comprising means to relatively rotate saidabrading element and work carrier, mechanism to cause a relativeapproaching and receding movement between said abrading disk and workcarrier, and an electrical control device including a time delay relaywhich is actuated by' the relative approaching movement between saiddisk and carrier to automatically cause a separation of said disk andwork carrier and to stop the rotation thereof when the abradingoperation has continued to the desired extent.

12. An abrading machine having a pair of op posed abrading disks and awork cage therebetween which is arranged to support a plurality ofpieces of work, means to rotate said disks and cage relative to eachother, a power actuated mechanism to cause a relative approachingmovement between said disks to bring said elements into operativerelation with the work to be abraded, means to apply a predeterminedpressure between said disks and the work, and electrically actuatedmeans controlled by the ap proaching movement between said disks toautomatically separate said disks after a predetermined period ofabrading.

13. An abrading machine having a rotatable abrading disk and a workcarrier comprising means to relatively rotate said disk and carrier,power actuated means to cause a relative approaching and recedingmovement between said disk and carrier, means including a manuallyengageable clutch to cause a rotation of said abrading disk and carrier,means including a manually operable control mechanism to cause anapproaching movement between said abrading disk and carrier, a controldevice for said mechanism including a time delay device, means actuatedby the relative approaching movement between said abrading disk andcarrier to actuate said time delay device, and means actuated by saidtime delay device including a solenoid which is operatively connected toreverse the direction of movement of the power actuated means to cause arelative separation between the abrading disk and the carrier, and asecond solenoid operated simultaneously with the first to disengage theclutch and stop the movement of the abrading disk and the carrier.

14. An abrading machine having a rotatable abrading disk and a workcarrier comprising means to rotate said abrading disk and carrierrelative to each other, means including a manually controlled, poweractuated mechanism to raise and lower said abrading disk relative tosaid carrier to position the disk in operative contact with the surfaceof the work, means to apply a predetermined pressure between saidabrading disk and carrier to cause the desired abrading action, anelectrically controlled mechanism including contact members actuated bythe approaching movement between said disk and carrier, a time delayrelay, connections between said contact members and said relay to causesaid relay to become effective after a predetermined approachingmovement between said disk and carrier, and electrically controlledmeans actuated by said relay after a predetermined period of abrading toautomatically separate the abrading disk and the carrier.

15. A lapping machine comprising two 'opposed' laps which are relativelyrotatable, a work cage therebetween arranged to hold a multiplicity ofwork pieces in lapping contact with the laps, means to cause a relativerotary movement between the work cage and laps to lap the work pieces,and mechanism acting automatically to stop the relative rotary lappingmovement of the laps and cage after the laps have reached apredetermined distance apart.

16. A lapping machine of the type covered by claim 15 comprising a timedelay device and mechanism controlled thereby which serves after thelaps have reached a predetermined distance apart to cause apredetermined lapping operation and thereafter separate the laps.

17. An abrading machine having a pair of opposed abrading disks and awork cage for supporting a plurality of work pieces therebetweencomprising means for relatively rotating said disks, means for movingsaid cage to carry the work pieces through an irregular path betweensaid disks, means whereby the disks may approach each other and abradethe work pieces, an electrical control system including a timedelaydevice, and means actuated by the relative approaching movement of saiddisks to actuate said timing device when the laps are a predetermineddistance apart which serves after a predetermined time interval to causea relative separation of the disks and to stop the rotation of the disksand the cage.

18. An abrading machine having a pair of opposed abrading disks and awork cage for supporting a plurality of work pieces therebetweencomprising means for relatively rotating said disks, means for movingsaid cage to carry the work pieces through an irregular path betweensaid disks, power actuated means to cause a relative approachingmovement between said disks, an electrical control system including atime delay device, and means actuated by the relative approachingmovement of said disks to actuate said timing device which serves aftera predetermined time interval to cause a relative separation of thedisks and to stop the rotation of the disks and the cage.

19. An abrading machine comprising a pair of opposed abrading disks anda work cage therebetween which is arranged to support a plurality ofpieces of work in operative relation with said opposed disks comprisingmeans to rotate said disks, means to move said cage so as to carry thework pieces through an irregular path between the opposed disks, poweractuated means to cause a relative approaching movement between saiddisks to bring them into abrading engagement with the work pieces, meansto apply a predetermined pressure between said opposed disks and thework to cause the desired abrading 1 disks relative to each other, meansto move the cage through an irregular path between the opposed faces oi.said disks, means including a manually controlled, power actuatedmechanism to raise and lower one of said disks to position the disk inoperative contact with the surface of the work, means to apply apredetermined pressure 21. An abrading machine having a pair of opposedabrading disks and a work cage therebetween which is arranged to carry aplurality of work pieces between said disks, means including a clutch torotate said abrading disks relative to each other and to move said cagebetween the disks to carry the work pieces through an irregular path onthe abrading disks, a motor driven mechanism to cause a relativeapproaching and separating movement between said disks, manuallyoperable means to initiate an approaching movement thereof to bring thedisks into abrading engagement with the work pieces, a solenoid arrangedto reverse the motor driven mechanism for separating the disks, a secondsolenoid operatively connected to disconnect the clutch, an electricalcircuit including a time delay device and contact members actuated bythe relative approaching movement between said disks which is operativeafter a predetermined abrading period to energize said solenoid andthereby cause a separating movement between the disks and to stop therotation of the disks after the motion of the work carrying cage.

22. An abrading machine having a pair of opposed, relatively rotatableabrading disks and a work cage therebetween comprising power actuatedmeans to cause a relative approaching and receding movement between saiddisks, means including a manually engageable clutch to cause a rotationof said abrading disks and cage, means including a manually operablecontrol mechanism to cause an approaching movement between said disks, acontrol device for said mechanism including a time delay device, meansactuated by the relative approaching movement between said disks toactuate said time delay device, and means actuated by said timing deviceincluding a solenoid which is operatively connected to reverse thedirection of movement of said power actuated means to cause a relativeseparation between said abrading disks and a second solenoid operatedsimultaneously with the first to disengage said clutch and stop themovement of the disks and the cage.

RAYMOND A. COLE.

